When sending in my federal check, what else do I need to send in the envelope? My W2 hard copies? My voucher? Anything else

You would only include the payment voucher and the check.

Do not mail your W-2 forms if the return was successfully e-filed.  You would also not want to include a copy of your tax return.

Please see the article below for additional guidance.

https://ttlc.intuit.com/replies/4232263

Hello,

Please go through TurboTax FAQ page and see if it helps : https://ttlc.intuit.com/questions/2580011-how-do-i-pay-my-irs-tax-due-with-a-check-or-money-order

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